Actually, Jimmy Carter's tax credit was one of the few things that he did right. Believe me, I'm no Carter fan, but the tax credit for hiring people was actually responsible for 700,000 new jobs.
Of course, it's only a temporary fix, to kick-start hiring. In Carter's day the kick-start didn't work in the long run, because none of the other economic factors of a recovery were in place, unlike today, where all the factors are in place except unemployment.
As far as the "Across the board tax cut" statement goes:
If it works like it did for Reagan,
we will have another year-and-a-half of rising unemployment, and growing deficits due to lower revenue, before we start getting a jobs recovery.
And that doesn't sound good to me at all.